Structural characterization of the arboreal community of the tropical deciduous forest of cerro de la Cruz, El Salto, Jalisco

Abstract

The current investigation has the aim to characterize tropical deciduous forest in “cerro de la Cruz” area at El Salto, Jalisco.
Nineteen permanent sample plots were established, each of 500 m². All trees with DBH ≥ 7cm were registered; their species were identified, plus, the diameter at breast height, height and average canopy diameter were measured. Density, dominance, frequency, importance value index, Pretzsch stratification index, Shannon-Wiener index and Simpson index were calculated. Species richness resulted in 19 species, distributed in 18 genera and 10 botanical families. Density reached 349 Nha^-1 and basal area 4.347 m²ha^-1 . Diametric class distribution of the inferior classes showed a “J” inverted shape distribution, as a response of the forest dynamics to disturbances. Most ecological importance species were Pithecellobium dulce, Bursera
bipinnata, Heliocarpus terebinthinaceus, Agonandra racemosa and Annona longiflora due to their great abundance and resilience capacity. Pretzsch stratification index (A) showed that there is a heterogeneity occurring in the distribution of species by height layer (A= 1.023; A_MAX = 4.043) reaching only 31.11% of the maximum possible equitability. Diversity indexes indicated a low diversity (H´= 1.067 y ʎ = 0.104) compared to others sites nationwide. It was determined that the conservation status of this forest is a secondary succession, due to factors such as wildfires, livestock, and the high occurrence of shrub and herbaceous species, so it is important to start a line of action focused on restoration and recovery of this ecosystem.